The aim of the present study was to determine the apparent and true digestibilities of amino acids of maize, low tannin sorghum, pearl millet and finger millet in adult caecectomized cockerels. Adult cockerels (n = 60), 25-weeks old, were used in this study of which 30 birds were caecectomized as per a standard method. The apparent digestibilities of amino acids of sorghum were not affected by caecectomy, but were higher for maize, finger millet and pearl millet in caecectomized cockerels. Caecectomy had no influence on the true digestibilities of amino acids of maize, but higher digestibilities were observed for most of the amino acids of sorghum and finger millet in caecectomized cockerels. Caecectomy lowered the true digestibility of cystine, threonine and serine of pearl millet. The apparent digestibilities of amino acids of maize, finger millet and pearl millet were underestimated in intact cockerels. The true digestibilities of most of the amino acids of sorghum and finger millet were underestimated, while those of cystine, threonine and serine of pearl millet were overestimated in intact cockerels. The findings suggest that the amino acid digestibility values of cereal grains determined using caecectomized cockerels might be appropriate and reliable for poultry diet formulations. Moreover, the digestibilities of amino acids of finger millet were inferior to other cereal grains, while those of pearl millet were comparable to maize and sorghum.